1. Field of the Invention
This invention relates to a sound absorber supporting structure of an air intake box for selectively introducing inside air or outside air into an automotive air conditioner.
2. Description of the Prior Art
Automotive air conditioners such as that shown in FIG. 1 are known, which comprise an air intake box I including an air intake door 1 adapted to switchingly effect outside air introduction or inside air circulation, and a blower 2; a cooling unit C including an evaporator 3 for causing a coolant to be evaporated during cooling operation; a heater unit H including a heater core 4 through which cooling water heated by the engine is circulated; and an air mix door 5 arranged to control the quantity of air passed to the heater core.
In the air intake box I provided in the foregoing conventional automotive air conditioner, as shown in FIGS. 2 and 3, an electric motor 8 is mounted on a bracket 7 fixedly attached to the bottom of a blower housing 6; the blower 2 is mounted at the upper end of the rotary shaft of the motor 8 and accommodated in the blower housing 6; and a cooling duct 10 is connected at one end thereof to the aforementioned bracket 7 and extended as far as the motor 8. Furthermore, in order that acoustic vibration or sound are not perceived as noise in the vehicle compartment, a pair of sound absorber membranes 15, which may be formed by compression-molding of glass fiber or the like into a rectangular shape, are provided on the inner surfaces of left and right side walls 13 of an inside air--outside air changeover unit 11, as shown in FIGS. 2 and 3. Denoted at 14 are inside air inlet ports formed in a part of the inside air--outside air changeover unit 11.
With the aforementioned conventional arrangement, however, difficulties have been experienced in mounting the sound absorber membranes 15. Such membranes are adhered directly to the inner surfaces of the left and right hand side walls 13 of the inside air--outside air changeover unit 11 by applying an adhesive agent onto one surface of each membrane 15. Another disadvantage is such that the sound absorber membranes 15 tend to peel off the respective side walls 13 due to aging of the adhesive agent. If the sound absorbers should peel off, then the air intake door 1 would possibly be immovably caught by the membranes so that the silencing effect would significantly be decreased.